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1.
Xiao-jing Wang Xu-li Li Chao Liu Fa-tang Li Yu-pei Li Jun Zhao Rui-hong Liu Guo-dong Li 《International Journal of Hydrogen Energy》2018,43(1):219-228
The development of high-efficiency and low-cost photocatalysts in photocatalytic H2 evolution systems from water remains challenging. The substitution of a noble metal as the co-catalyst is still one of the important and meaningful issues in this field. Herein, we report a series of CaIn2S4 catalysts combined with Ni2P, which acts as the co-catalyst, for boosting photocatalytic hydrogen evolution under visible light. The integrated system of the Ni2P/CaIn2S4 composite exhibited high efficiency and durability, which were even higher than those of Pt decorated catalysts. The promoting effect of Ni2P can be ascribed to its excellent reductive ability and analogous metallic character, which can accelerate the transfer and consumption of the photo-generated electrons. Moreover, based on the surface photo-voltage technique and electrochemical tests, the unique mechanism of Ni2P for the movement of photo-generated charges during the photocatalysis process is proposed for the first time. 相似文献
2.
《International Journal of Hydrogen Energy》2019,44(4):2323-2329
In this work, carbon encapsulated RuO2 nanorods (RuO2 NRs/C) has been synthesized by thermolysis of ruthenium chloride and Punica granatum (P. granatum) peel under N2 atmosphere. The synthesized RuO2 NRs/C was characterized using Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction method (XRD), field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) with energy dispersive spectroscopy (EDS) analyses. The FT-IR results suggested that the organic constituents of P. granatum have been carbonized and encapsulated over RuO2 nanorods (RuO2 NRs). The XRD pattern of RuO2 NRs/C revealed its crystalline nature and carbon encapsulation. The synthesized RuO2 NRs/C has been well dispersed with the average width of 20 nm, exposed from the FE-SEM and HR-TEM images. The EDS results of RuO2 NRs/C showed the existence of three elements viz., Ru, O and C. Further, the supercapacitor and electrocatalytic hydrogen evolution reaction (HER) activities of RuO2 NRs/C were studied using standard electrochemical methods. The synthesized RuO2 NRs/C offered a maximum specific capacitance of 151.3 F g−1 at a scan rate of 5 mV s−1, obtained from the cyclic voltammetry results. The onset over potential and Tafel slope of synthesized RuO2 NRs/C for HER were −0.099 VRHE and −99.4 mV dec−1, respectively. The present study revealed that RuO2 NRs/C as a better candidate for supercapacitor and HER. 相似文献
3.
《International Journal of Hydrogen Energy》2020,45(1):443-451
Walnut Shell-derived hierarchical porous carbon has been successfully synthesized by the efficient KOH activation process. The hierarchical porous carbon material activated at 600 °C, has the specific micropore area of 1037.31 m2 g−1 and micropore volume of 0.51 cm3 g−1, which leads to have electrochemical performances of the hydrogen evolution reaction (HER) and supercapacitors. Specifically, as the hydrogen evolution reaction electrocatalyst, the walnut shell-derived carbon material activated at 600 °C exhibits a lower onset potential of 6.00 mV, a smaller Tafel slope of 69.76 mV dec−1 and outstanding stability above long-term cycling. As a supercapacitor electrode material, the sample possesses specific capacitance of 262.74 F g−1 at 0.5 A g−1, the remarkable rate capability of 224.60 F g−1 at even 10 A g−1 and good long-term stability. A symmetric supercapacitor shows the highly energy density of 7.97 Wh kg−1 at a power density of 180.80 W kg−1. This novel and low-cost biomass material is very promising for the electrocatalytic water splitting and supercapacitors. 相似文献
4.
Kewei Wang Jinshan Tan Zejia Lu Shuai Chen Xilin She Huawei Zhang Dongjiang Yang 《International Journal of Hydrogen Energy》2018,43(30):13939-13945
The preparation of hydrogen evolution reaction (HER) electrocatalyst with high catalytic performance is a huge challenge. In this work, we develop a MoP/Fe2P/RGO composite as a electrocatalyst for HER. The MoP/Fe2P/RGO exhibits excellent electrocatalytic performance with a Tafel slope and an onset overpotential of 51 mV/dec and 105 mV, respectively. To drive 10 mA/cm2, it only requires a small over-potential of 156 mV. The high electrocatalytic HER activity is mainly due to the synergistic effect of MoP and Fe2P. In addition, the introduction of RGO not only prevents particle aggregation and coalescence during high temperature phosphating, but also improves the conductivity of the catalyst. 相似文献
5.
Recently, the first-row transition metal dichalcogenides MX2 (M = Fe, Co, Ni; X = S, Se) have been widely reported as promising catalysts for hydrogen evolution reaction (HER) because of its excellent catalytic activity and earth-abundance. The rational nanostructure designs have been proved as an effective way to improve their catalytic performance. However, the reported one dimension (1D) NiS2 nanowires for HER suffer from a large Tafel slope. Here, we report a facile synthesis of 1D NiS2 nanowires and its high efficient catalytic activity in HER. This nanowire structure with large surface area and active sites enables highly efficient electrocatalytic performance in HER with a much smaller Tafel slope (83.5 mV/dec) compared to that of bulk NiS2 (136 mV/dec) as well as long-term stability. Our work builds up a structure–performance relationship and enriches the synthetic strategy to other efficient catalysts such as first-row transition metal dichalcogenides or transition metal phosphide. 相似文献
6.
《International Journal of Hydrogen Energy》2019,44(59):30876-30884
Hydrogen production from water splitting through electrocatalytic or photoelectrochemical route shows great potential for renewable energy conversion. Herein, the plasmon-enhanced photoelectrical nanocatalysts (NCs) have been successfully developed by Au nanoparticle-decorated Bi2Se3 nanoflowers (Au@Bi2Se3 NFs) as catalysts for hydrogen evolution reaction (HER), leading to a more than 3-fold increase of current under excitation of Au localized surface plasmon resonance (LSPR) and affording a markedly decreased overpotential of 375 mV at a current density of 10 mA cm−2. The HER enhancement can be largely attributed to effective electron-charge separation and the increase of carrier density in Bi2Se3 induced by the injection of hot electrons of Au nanoparticles. Meanwhile, Bi2Se3 nanoflowers (NFs), a kind of topological insulators, possess gapless edges on boundary and show metallic character on surface, providing a path for the flow of electrons in the electrocatalytic system. This study opens up a new avenue towards the design of higher energy conversion catalytic water splitting systems with the assistance of light energy, which could increase of HER catalysis efficiency by plasmonic excitation. 相似文献
7.
《International Journal of Hydrogen Energy》2023,48(45):17014-17025
Functionalized carbon based 2D materials are promising candidates for low cost and environment friendly electrocatalyst for hydrogen evolution reaction (HER) and supercapacitor applications. To overcome the limitations posed by the noble metals and transition metal based composites, we have successfully synthesized metal free polysulfide functionalized reduced graphene oxide (GPS) in a simple chemical route. Structure and morphology of the material are characterized via XRD, FTIR, Raman, TEM, XPS measurements. The material behaves as an efficient HER electrocatalyst in acidic medium as well as energy storage device. It shows an onset potential of 97 mV and overpotential of 254 mV to reach a high current density of 10 mA/cm2. DFT calculations are carried out to understand the structural stability and identification of active sites of the material. Boosting catalytic activity via increasing the number of active sites is an elegant approach. In this material we have used the S atoms of polysulfide polymer to facilitate hydrogen adsorption and desorption, thus improving the hydrogen evolution ability. The supecapacitor attains the high specific capacitance 347 F/g at the current density of 1 A/g. The origin of such performances is due to synergistic effect of both the graphene network and the polysulfide functionalizations. 相似文献
8.
Lulu Chen Wenxiu Yang Xiangjian Liu Jianbo Jia 《International Journal of Hydrogen Energy》2017,42(17):12246-12253
Molybdenum sulfide (MoS2) has received tremendous attracts for its promising performance in the aspects of hydrogen evolution reaction (HER). To improve the HER activity of MoS2, we designed a flower-shaped CoS2/MoS2 nanocomposite with enhanced HER electroactivity compared with MoS2 nanosheets by a simple one-step hydrothermal method. The facile approach brings about distinct transformation of the morphology from nanosheets to nanoflower structures. The introduction of Co element into MoS2 results in the larger active surface area, more edge-terminated structures, and higher conductivity of the CoS2/MoS2 nanocomposite, which are good for improving the HER electroactivity. In brief, the optimized catalyst exhibits the low overpotential of 154 mV at 10 mA cm?2, small Tafel slope of 61 mV dec?1, and excellent stability in acidic solution. 相似文献
9.
《International Journal of Hydrogen Energy》2023,48(10):3849-3861
Transition metal doping is an effective method to induce a structural phase transition and improve the electrocatalytic performance of transition metal chalcogenides (TMDs). In this study, MoxRe1-xS2 nanosheets with Mo fraction x from 0 to 1 were grown on a carbon nanotube/carbon cloth (CNT@CC) substrate using a hydrothermal method by changing the molar ratio of Na2MoO4·2H2O to NH4ReO4 in the precursor solution. The effect of the Mo fraction x on the phase structure and electrocatalytic performance for the hydrogen evolution reaction (HER) of MoxRe1-xS2 nanosheets was studied. The results indicated that MoxRe1-xS2 consists of the 1T′ phase (Re, Mo)S2 and the 2H phase (Mo, Re)S2, and the proportion of the 1T′ phase is in the range of 40–50%. Mo0.5Re0.5S2/CNT@CC shows the best HER catalytic activity with an overpotential of 85 mV at a current density of 10 mAcm?2, a Tafel slope of 38 mV dec?1 and a charge transfer resistance of 1.04 Ω. This excellent HER catalytic activity is attributed to the phase transition, defects and S vacancies on the basal planes, as well as the synergistic effect between the MoxRe1-xS2 nanosheets and CNT. 相似文献
10.
《International Journal of Hydrogen Energy》2019,44(52):28151-28162
The reduction of active sites due to reunion and slow electron transfer rates and low electronegativity greatly reduced the catalytic performance of many two-dimensional materials. In this paper, we synthesized composites for partially reducing graphene oxide and molybdenum disulfide (MoS2@prGO) by one-step hydrothermal method. With the addition of triethanolamine, MoS2 is highly dispersed on the prGO carrier and converted into the 1T phase MoS2 (50.4%). Meanwhile, it helps to increase the electron transfer rate of the MoS2@prGO composites. MoS2@prGO composites presents a high electron cloud density due to the existence of N atoms and prGO, which promotes the occurrence of hydrogen ion conversion hydrogen reaction and decreases the electrocatalytic hydrogen evolution overpotential. MoS2@prGO composites exhibits an overpotential of 263 mV at 10 mA/cm2 and a small Tafel slope of 60 mV/dec. This work is devoted to offer a new prospect and direction for the improvement of electrochemical HER performance. 相似文献
11.
Peng Zhu Yu Chen Yu Zhou Zhixiong Yang Di Wu Xiang Xiong Fangping Ouyang 《International Journal of Hydrogen Energy》2018,43(31):14087-14095
Defect-rich MoS2 nanosheets are vertically grown on graphene-protected Ni foam by a facial hydrothermal route. The vertically aligned MoS2 nanosheets with defects such as cracks, amorphousness and oxygen-incorporated disorders endow these as-synthesized catalysts with rich active sites, high conductivity and good stability. The graphene deposited on Ni foam increases its stability in acid. The optimized catalyst exhibits high activity for hydrogen evolution with a quite low overpotential of 140 mV at 10 mA cm?2, a small Tafel slope of 42 mV decade?1, and a large exchange current density of 63 μA/cm2, as well as excellent stability. This performance is superior to most of its analogue MoS2 and many transition metal sulfides. This work will broaden the vision to improve the activity of self-supported electrocatalysts by carefully designing the anchored catalysts. 相似文献
12.
Wenjun Zhao Mengying Li Huimin Wu Chuanqi Feng Guangxue Zhang 《International Journal of Hydrogen Energy》2018,43(28):12653-12660
Nickel selenides with different Ni/Se atomic ratio have been successfully synthesized by a simple solvothermal method. Among them, the nonstoichiometric compound (Ni0.85Se) (A-10) behaved excellent electrochemical catalytic activity towards hydrogen evolution reaction. Furthermore, it presents an ultra-low overpotential (η) of 190 mV and extremely small Tafel slope of 57 mV/dec when the current density jA reaches ~10 mA/cm2. At the same time, it has large effective electrochemical active surface area and shows outstanding stability after a long time chronoamperometry testing. 相似文献
13.
Hongxing Dong Ting LeiYuehui He Nanping XuBaiyun Huang C.T. Liu 《International Journal of Hydrogen Energy》2011,36(19):12112-12120
Porous Ni3Al intermetallic material with a mean pore diameter of around 1 μm was prepared by step sintering Ni and Al powder pressed compacts in vacuum furnace at 900 °C. The electrocatalytic activity of the as-fabricated porous Ni3Al material as an electrode for hydrogen evolution reaction (HER) in alkaline solutions was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) techniques. It is found that the onset potential of porous Ni3Al for HER shifted in the positive direction favoring hydrogen generation with lower overpotential, compared with foam Ni and dense Ni electrodes. Effects of electrolyte concentration and temperature on HER as well as the electrochemical stability in alkaline solution were investigated and the electrochemical activation energy was determined for the porous Ni3Al. The increased activity for HER was attributed to the high porosity, an increased electrochemical surface area and the nanostructure of porous Ni3Al electrode. The corrosion tests showed that the corrosion resistance of porous Ni3Al electrode changed during the immersion process due to the formation of passive film layers. 相似文献
14.
《International Journal of Hydrogen Energy》2022,47(8):5319-5325
The fabrication of metal sulfides heterostructure is a promising strategy for enhancing catalytic activity. Herein, the MoS2/CuS heterostructure was successfully grown on carbon cloth (MoS2/CuS/CC) through an efficient method. The SEM results confirmed that the fabricated MoS2/CuS/CC composites have a flake morphology, which can not only improves the surface area but also offers ample surface catalytic active sites. Particularly, the optimized MoS2/CuS/CC-2 electrocatalyst showed a small overpotential of 85 mV@10 mA cm?2 and exceptional long-term cycling durability for hydrogen evolution in 1 M KOH. The outstanding catalytic activity is attributed to the fact that the combination of MoS2 with CuS can greatly enhance the charge transport rate and improve the structural stability. These results suggest that the MoS2/CuS/CC heterostructure is a potential electrocatalyst for hydrogen production. 相似文献
15.
《International Journal of Hydrogen Energy》2023,48(43):16279-16285
Developing efficient and low-cost electrocatalysts for hydrogen evolution reaction (HER) is important for hydrogen fuel production. In this study, we synthesized two different types of CoS2 under low sulfur (LS) and high sulfur concentration (HS) conditions. Structural analysis results show that CoS impurity phase forms easily when the concentration of sulfur is low, while at high sulfur concentration the growth of CoS impurity phase is inhibited and leads to phase-pure CoS2. Electrochemical investigation of HER performance reveals that the onset potential of CoS2 (HS) electrode (ca. − 0.11 V vs. the reversible hydrogen electrode, RHE) is 30 mV anodic of the CoS2 (LS) one (ca. − 0.14 V vs. RHE). At a specific current density of 10 mA cm−2 the required overpotential on CoS2 (HS) electrode is only 163 mV, which is 40 mV less than the CoS2 (LS) electrode. Electrochemical impedance spectroscopy (EIS) data further demonstrate that the charge transfer rate of CoS2 (HS) electrode is faster than that of CoS2 (LS) electrode towards HER. 相似文献
16.
Zhuo Guo Tianshuai Sun Yahui Li Hailan Kang Yuhan Che Yan Zhang Jinlin Lu 《International Journal of Hydrogen Energy》2018,43(51):22905-22916
In this work, mesoporous WS2 with high surface area was prepared by hard template method. First, a one-step nanocasting generates metal precursor@mesoporous silica SBA-15 composites. A hydrothermal method is subsequently adopted to convert the precursors to sulfides in the confined nanochannels. After etching silica SBA-15, mesoporous layered metal sulfide crystals were obtained as the products. Then, we have put forward a new catalyst based on mesoporous WS2, RGO nanosheets and Pt nanoparticles as a highly efficient electrocatalyst for hydrogen evolution. The Pt/WG-2 nanostructure electrocatalyst in this report exhibits excellent performance with a small Tafel slope of 47 mV dec?1, long-term durability and an overpotential of 95 mV in 0.5 M H2SO4 for the hydrogen evolution reaction (HER). 相似文献
17.
《International Journal of Hydrogen Energy》2019,44(2):965-976
In this study, conductive Ti3C2 MXenes were used as a promoter to accelerate charger transfer of MoS2, realizing highly efficient HER electrocatalysis. A facile hydrothermal strategy is demonstrated to be effective for in situ growth of MoS2 nanosheets vertically standing on planar Ti3C2 nanosheets to form hierarchical heterostructures. Beneficial from the opened layer structures and strong interfacial coupling effect, the resulting MoS2/Ti3C2 heterostructures achieve a giant enhancement in HER activity compared with pristine MoS2 nanosheets. More specifically, the catalytic current density induced by MoS2/Ti3C2 heterostructures at an overpotential of ∼400 mV is nearly 6.2 times as high as that of the pristine MoS2 nanosheets. This work uncovers that the Ti3C2 nanosheets are ideal candidates for construction of highly active electrocatalysts for water splitting. 相似文献
18.
《International Journal of Hydrogen Energy》2019,44(42):23547-23555
Molybdenum disulfide (MoS2) and its composites are the promising electrocatalysts for the hydrogen evolution reaction (HER) in acidic solution because it is earth-abundant and low-cost. Here we reported the ultrathin molybdenum disulfide nanosheet-coated acetylene black (AB) coated (MoS2@AB) as the electrocatalysts for the HER. The catalysts were synthesized in a facile one-pot solvothermal route. The as-prepared catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution TEM, X-Ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The results show that the MoS2 nanosheets on AB have a few layers and many surface defects, which are benefical to the HER catalysis. Electrochemical tests revealed that the existence of AB can't only make the catalyst expose a considerable amount of active sites but also increase the turnover frequency (TOF) value per site. In addition, the MoS2@AB(75) had excellent electro-catalytic HER performances with a low onset potential (−110 mV), a small Tafel slope (50–60 mV per decade) and the longtime stability (10 h). 相似文献
19.
Xianpei Ren Qiang Ma Pinyun Ren Yonghua Wang 《International Journal of Hydrogen Energy》2018,43(32):15275-15280
Benefiting from improved electrical conductivity, the N-doped MoSe2 nanosheets show substantially enhanced HER activity with a lower onset overpotential of approximately ?135 mV and a smaller Tafel slope of 62 mV dec?1, which exhibiting enhanced catalytic performance compared with that of pure MoSe2. The success of improving the HER performance via the introduction of N dopant offers a new opportunity in the development of high performance MoSe2-based electrocatalyst. 相似文献
20.
《International Journal of Hydrogen Energy》2023,48(76):29552-29564
Synthesis of efficient electrocatalysts for energy applications is a major area scientists are currently focusing on to address the twin challenges of energy shortfall and the production of clean energy. Herein, an efficient electrocatalyst, polyaniline incorporated with polyethylene glycol capped CuO/TiO2 is prepared, which is effective in hydrogen evolution reactions and energy storage applications. The characterizations like XPS, XRD, FT-IR, FE-SEM, HR-TEM, and BET have been carried out to confirm the successful formation of the synthesized PANI/CuO/TiO2 composite. At 10 mA/cm2 current density, the prepared composite exhibits a lesser overpotential of 536 mV and 1587.2 C/g at 1 A/g as the specific capacity. The electrode prepared using the PANI/CuO/TiO2 composite also shows cyclic stability up to 2000 cycles. The synthesized composite is an efficient electrocatalyst for energy related applications. 相似文献